Packet Send Issue

Everything works, but once building turrain gets close to being done it stops and does nothing. Does anyone know how to help me with this here?

PHP:

<?php

namespace PacketSend;

use pocketmine\event\entity\EntityLevelChangeEvent;
use pocketmine\event\Listener;
use pocketmine\plugin\PluginBase;
use pocketmine\entity\Entity;
use pocketmine\Player;
use pocketmine\network\protocol\StartGamePacket;
use pocketmine\event\player\PlayerJoinEvent;
use pocketmine\event\server\DataPacketReceiveEvent;
use pocketmine\event\server\DataPacketSendEvent;
use pocketmine\level\Position;
use pocketmine\level\Level;
use pocketmine\math\Vector3;
use pocketmine\utils\TextFormat as C;

class Main extends PluginBase implements Listener{
   
    public function onEnable(){
        $this->getServer()->getPluginManager()->registerEvents ($this, $this);
    }
   
    public function sendChangeDimension(Player $player, $dimension = 0) {
        echo "sendChangeDimension\n";
        $pk = new StartGamePacket();
        $pk->seed = - 1;
        $pk->dimension = $dimension;
        $pk->x = $player->x;
        $pk->y = $player->y;
        $pk->z = $player->z;
        $spawnPosition = $player->getSpawn();
        $pk->spawnX = (int) $spawnPosition->x;
        $pk->spawnY = (int) $spawnPosition->y;
        $pk->spawnZ = (int) $spawnPosition->z;
        $pk->generator = 1;
        $pk->gamemode = $player->gamemode & 0x01;
        $pk->eid = 0;
        $player->dataPacket($pk);
        $player->sendSettings();
    }
   
    public function onLevelChange(EntityLevelChangeEvent $event){
        $player = $event->getEntity();
        $pk = new ChangeDimensionPacket();
        $pk->eid = 0;
        $pk->dimensionId = 1;
        $this->sendChangeDimension($player, 1);
        $player->dataPacket($pk);
        $player->chunk = null;
        $player->checkNetwork();
    }
}

class ChangeDimensionPacket extends DataPacket {
   
    const CHANGE_DIMENSION_PACKET = 0xc1;
    const NETWORK_ID = self::CHANGE_DIMENSION_PACKET;
    public $eid;
    public $dimensionId;
   
    public function decode(){
        $this->dimensionId = (\PHP_INT_SIZE === 8 ? \unpack ("N", $this->get(4)) [1] << 32 >> 32 : \unpack ("N", $this->get (4)) [1]);
    }
   
    public function encode(){
        $this->buffer = \chr (self::NETWORK_ID);
        $this->offset = 0;
        $this->buffer .= \pack ( "NN", $this->eid >> 32, $this->eid & 0xFFFFFFFF );
        $this->buffer .= Binary::writeLong($this->eid);
        $this->buffer .= \chr( $this->dimensionId);
        $this->buffer .= \pack("N", $this->dimensionId);
    }
}